Pushbutton apparatus for radios and the like



Oct. 1, 1968 TAMAKI OHASHI 3,403,564

PUSHBUTTON APPARATUS FDR RADIOS AND THE LIKE Filed June 17, 1966 United States Patent PUSHBUTTON APPARATUS FOR RADIOS AND THE LIKE Tamaki Ohashi, 1629 Tanashi-shi, Tokyo, Japan Filed June 17, 1966, Ser. No. 558,309

Claims priority, application Japan, June 21, 1965,

9 Claims. (Cl. 74-1033) ABSTRACT OF THE DISCLOSURE A pushbutton apparatus having two displaceable rods with a setting plate on one which is locked in position by an initial setting and serves to reset a displaceable element to the same position. The rods are coupled together by a pin passing through slots in the rods to cause production of a transverse force on the rods when the setting plate is being set to eliminate any play or gap.

The present invention relates to pushbutton apparatus and more particularly to pushbutton-type tuners for use in car radios and the like.

Pushbutton apparatus is generally known as shown, for example, by US. Patent No. 2,659,236. This known apparatus may be of the type wherein, after a pushbutton at the front of a casing is pushed forwards and an adjustable setting plate is brought into engagement with a rotatable frame which moves a variable tuning element such as a core, the pushbutton is still further pushed, strongly, to bring a wedge-shaped cam into engagement with a locking member so that the setting plate is locked by the latter. The construction is such that a pushbutton rod having the pushbutton and the wedge-shaped cam fixed thereto is attached slidably to the rear end of a setting plate rod having on its side surface the aforesaid setting plate and the locking member. The setting plate is inserted at its rear end through a guide aperture for being supported slidably by the upper and lower edges thereof, but it often happens that there exists more or less of a gap or play in the upward and downward directions therebetween. Usually, however, this kind of tuning system is very sharp in selectivity and a desired frequency cannot be optimally tuned if the projecting and retracting position of the associated core in relation to the corresponding coil is wrong. Thus, for example, a misalignment in the order of mm. is quite undesirable even if a fine adjustment has been previously made. Accordingly, even if the setting plate is initially set accurately in the hitherto known type of apparatus, if the setting plate rod has any play in the upward and downward directions, an error in the engaging angle between the setting plate and the rotatable frame will be caused to an extent depending on the direction of the pushing force acting on the pushbutton rod. Thereby, the degree of rotation angle of the rotatable frame is inaccurate and the desired frequency cannot be properly tuned.

A principal object of the present invention is to provide a novel pushbutton apparatus which is free of the above defect.

According to the present invention, a pushbutton rod having a pushbutton fixed to the rear end thereof and a setting plate rod having on its side surface a setting plate, a locking member for locking said plate and a wedgeshaped cam for actuating said member are arranged in parallel with one another and independently supported to be slidable forwards and rearwards, and a pin projecting laterally from said cam is in engagement with an oblique slot made in the pushbutton rod so that a pushing force acting on the pushbutton rod serves to give through the pin and the slot a vertical-component force to the setting ice plate rod. According to another feature of the invention, the pin has a collar rotatably mounted thereon so that the same is in engagement through said collar with the engaging slot.

An embodiment of the invention will next be explained with reference to the accompanying drawing in which:

FIGURE 1 is a plan view of said embodiment in unlocked condition;

FIGURE 2 is a sectional view taken along line IIII in FIG. 1;

FIGURE 3 is a plan view, partly broken away, of the embodiment in locked condition;

FIGURE 4 is a sectional view taken along line IV-IV in FIG. 3;

FIGURE 5 is a perspective and exploded view of the apparatus; and

FIGURE 6 is a plan view of a modified form of the wedge-shaped cam portion of the same.

More particularly, the apparatus of the invention comprises a first slidable member 1 and a second slidable member 2. These two members 1 and 2 are arranged in parallel with one another and are independently supported, to be forwardly and rearwardly slidable, by a casing 3. Specifically, the rear end portions of these members 1 and 2 are inserted in a guide aperture 5 in a front wall 4 of the casing 3 to be slidably supported by upper and lower edges 6, while the front end portions of these members 1 and 2 are curved outwardly to form side.

arms 7 and 7 which are at their respective holes 8 and 8 slidably mounted on and supported by guide pins 10 projecting from a rear wall 9 of the casing 3. The apparatus further includes a return spring 11 for the second slidable member 2, and stop 12 for limiting the rearward movements of the members 1 and 2. Elements 12a are rubber pieces mounted thereon. It is unavoidable in this case that slidable members 1 and 2 each have more or less of a gap or play G in upward and downward directions relative to the guide aperture 5.

The first slidable member 1 is provided with a pushbutton 13 fixed to the rear end thereof and serves as a pushbutton rod. The second slidable member 2 is provided with a semi-circular form of a frequency tuning setting. plate 14 rotatably attached by a pin 15 on the side surface thereof and serves as a setting plate rod. The setting plate rod 2 also has a locking mechanism, which comprises a wedge-shaped cam 16 slidable forwards and and rearwards and a lever-shaped locking member 18 adapted to be inclined by said cam 16. The lever 18 when inclined serves in turn to push the setting plate 14 through the intermediary of an outer resilient plate 17 from the outside to restrain the same from rotating.

The setting plate rod 2 has laterally extending upper and lower side plates 2a and 2a forming a channel shape, and the locking member 18 is attached thereto by pin 19. The locking member 18 has a tail 18a made of resilient strip material and the terminal end 18b thereof is curved into a V shape and is usually in contact with the outer side surface of the rod 2.

The setting plate 14 is to cooperate with a rotatable frame 20 provided in front of the same in generally the same manner as in the conventional structure, so that further explanation in this respect will not be necessary.

The wedge-shaped cam 16 is mounted on the side surface of the setting plate rod 2 in such a manner as to be slidable forwardly and rearwardly, but it is notmovable upwardly and downwardly. To this end, a pair of front and rear pins 21 and 22 projecting laterally therefrom are in engagement with a longitudinal slot 23 in the rod 2. Otherwise, as in the modification shown in FIG. 6, the cam 16 is Supported at its upper and lower projections 24 by the inner surfaces of the upper and lower side plates 2a, with the rear side pin 22 being omitted.

The front side pin 22, in either case, is further extended in length to be inserted in and engaged with an oblique slot 25 made in the pushbutton rod 1. It is preferred that the pin 22 have collars 26 and 27 rotatably mounted thereon and be engaged at those collars 26 and 27 in their slots 23 and 25, whereby the movement of the pin 22 in relation to the slots 23 and 25 is smooth and defacement of these parts can be diminished.

The operation of the apparatus which will next be explained is as follows:

If, from the condition shown in FIG. 1 or in FIG. 2, a pushing force P is acted on the rear end of the pushbutton rod 1 toadvance the same, the setting plate rod 2 is pushed thereby to move forwardly and the advance thereof is stopped at the position where the setting plate 14 is brought into engagement with the rotatable frame 20. If, then, the pushbutton rod 1 is further pushed forwardly, the wedge-shaped cam 16 is forced to enter into the tail 18a of locking member 18 to incline the member 18. The setting plate 14 is thereby held at the assumed angular position. Thus, the setting plate 14 remembers the desired frequency for the next operation. While the setting is being effected, the pushing force P acting on the rear end of the pushbutton rod 1 serves to impart, due to the oblique slot 25 and the pin 21, a vertical-component force V, as clearly shown in FIG. 4, to the setting plate rod 2 so that the rod is pressed against the lower edge 6 to eliminate any gap or play G at that portion.

This eflfect is entirely the same even when the pushing force P is deflected or inclined more or less upwardly or downwardly. Thus, the setting plate rod 2, at setting, is always under the proper condition, namely it is pressed against one side edge 6 by the force V even if the pushing force P is deflected upwardly or downwardly.

The pushbutton rod 1 and the setting plate rod 2 are thus locked together through the wedge-shaped cam 16 and these are returned to the position shown by dotted lines in FIG. 3 by the action of the return spring 11 when released from the pushing force P. They are then in readiness for subsequent frequency selecting operations.

If, subsequently, a pushing force P is applied to the rear end of the pushbutton rod 1 to advance the same against the action of the spring 11, the setting plate rod 2 advances therewith. The setting plate 14 strikes against the rotatable frame 20 to rotate the same to the predetermined angular setting, as established in the initial memory operation. It is also true in this case that, regardless of the direction of the pushing force P, the setting plate rod 2 is given through the slot 25 and the pin 21 is vertical component force V and is pressed against the lower side edge 6, so that the same condition as in the setting operation can be obtained. Thereby, all influence of any play or gap G is eliminated.

Thus, according to the present invention, the setting plate rod when operated is always given a vertical component force in the same direction, so that the same may be operated as though under the condition where there exists no play or gap. Thus, the pushbutton apparatus of the invention is free of the defect of the conventional apparatus described above.

What is claimed is:

1. Apparatus for repeatedly positioning a displaceable element in the same position through a sequence of operations after an initial setting, said apparatus comprising push-button means, guide means guiding said pushbutton means for generally linear reciprocal displacement between inactive and operative stations in order to eifect said sequence of operations, settable means displaceable with and relative to said pushbutton means, locking means to lock said settable means to said pushbutton means to prevent relative movement therebetween when said settable means has assumed a desired attitude relative to the displaceable element with the pushbutton means in operative station, and accuracy insuring means effective on operation of the pushbutton means to exert a force on the same transverse to said linear displacement to bring the pushbutton means to fixed attitude relative to said guide means whereby to avoid the effect of incidental displacement therebetween, said pushbutton means comprising pushbutton and setting plate rods adapted for parallel displacement, said settable means including a setting plate rotatably mounted on the setting plate rod and adapted to engage said displaceable element, said locking means including a lever and wedge arrangement whereof the lever is displayed by the wedge, upon actuation by the pushbutton rod, to lock said setting plate in position, said accuracy insuring means including a pin and slot combination whereof the pin is connected to said wedge and is accommodated in a further slot provided in the setting plate rod to guide the wedge in movement relative to the latter, the slot of said pin and slot combination accommodating said pin and being disposed at an angle relative to said linear displacement whereby a transverse force can be exerted on said pushbutton rod.

2. Apparatus as claimed in claim 1 wherein the slots are in angularly intersecting relation, the slot in the setting plate rod being parallel to said linear displacement.

3, Apparatus as claimed in claim 2 comprising collars on said pin engaging in said slots.

4. Apparatus as claimed in claim 3, wherein said rods include end flanges, comprising further guide means engaging said flanges for guiding independent movement of the rods in parallel relation.

5. Apparatus as claimed in claim 4 comprising a further lever on and adapted to sandwich the setting plate in locked relation against said setting plate rod, said setting plate rod including side plates defining a channel, said locking means including a locking member pivoted to said side plates and adapted for engaging said further lever, said locking member supporting the first said lever in a position to be engaged by and displaced by said wedge.

6. Apparatus as claimed in claim 5 wherein the pin and wedge hold the rods together while permitting slidable displacement therebetween.

7. Apparatus as claimed in claim 6 comprising a return spring engaging said setting plate rod and efiective therethrough to return said pushbutton rod to inactive station.

8. Apparatus as claimed in claim 7 wherein the slot in the setting plate rod is an open-ended slot.

9. Apparatus as claimed in claim 8 wherein said further lever is a resilient means which prior to the locking of said setting plate pivots said locking member in such a manner that the first said lever is in a position of interference with said wedge whereby movement of the pushbutton rod towards said active station is effective through said pin and slot combination and wedge to carry along said setting plate rod until the setting plate is brought against said displaceable element.

References Cited UNITED STATES PATENTS 2,928,283 3/1960 Teaf 74l0.33

MILTON KAUFMAN, Primary Examiner. 

